When to train at singapore?

I'm a 51 cleric currently training on wraiths, and i was wondering when training on the ghosts in singapore will be better exp than wraiths.

Jr Selkies in the ghost ship offer about 30% an hour at your lvl without 2x ;-)

It also depends on your build and strength of your gear, because I started training at wraiths at level 36 with my new cleric, and probably will hit up the ghost ship by 43 when I get my lama staff. So to ask when you should be going there is kind of vague due to the fact that only YOU will know when it is right for you [which requires testing].